fixed nullpointer at startup

brouter-routing-app/src/main/java/btools/routingapp/AppLogger.java

@@ -3,6 +3,8 @@ package btools.routingapp;
 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.util.Date;
 
 import android.os.Environment;
@@ -61,8 +63,20 @@ public class AppLogger
         }
         catch( IOException e )
         {
-          throw new RuntimeException( "cannot write appdebug.txt: " + e );
+          throw new RuntimeException( "cannot write brouterapp.txt: " + e );
         }
       }
     }
+
+    /**
+	 * Format an exception using 
+	 */
+    public static String formatThrowable( Throwable t )
+    {
+      StringWriter sw = new StringWriter();
+      PrintWriter pw = new PrintWriter( sw );
+      t.printStackTrace( pw );
+      return sw.toString();
+    }
+
 }

brouter-routing-app/src/main/java/btools/routingapp/BRouterActivity.java

@@ -56,6 +56,7 @@ public class BRouterActivity  extends Activity implements OnInitListener {
 
         // instantiate our simulation view and set it as the activity's content
         mBRouterView = new BRouterView(this);
+        mBRouterView.init();
         setContentView(mBRouterView);
     }
 

brouter-routing-app/src/main/java/btools/routingapp/BRouterView.java

@@ -83,7 +83,10 @@ public class BRouterView extends View
 
         public BRouterView(Context context) {
             super(context);
+        }
         
+        public void init()
+        {
             DisplayMetrics metrics = new DisplayMetrics();
             ((Activity)getContext()).getWindowManager().getDefaultDisplay().getMetrics(metrics);
             imgw = metrics.widthPixels;
@@ -218,6 +221,10 @@ public class BRouterView extends View
               String msg = e instanceof IllegalArgumentException
                     ? e.getMessage() + ( cor == null ? "" : " (coordinate-source: " + cor.basedir + cor.rootdir + ")" )
                     : e.toString();
+                    
+              AppLogger.log( msg );
+              AppLogger.log( AppLogger.formatThrowable( e ) );
+
               ((BRouterActivity)getContext()).showErrorMessage( msg );
             }
             waitingForSelection = true;